Correction to “The High-Temperature Polymorph of LiBF₄”

sı Supporting Information I n our assignment of the space group of the high- temperature polymorph LiBF 4 , 1 an additional 6 2 screw axis was missed and has now been noticed, and the space group is here corrected from C222 as given in the original report to P6 2 22.As illustrated in Figure 1, the interior of the unit cells of both polymorphs contain two intertwined [Li-F-B-F] n helices, with each individual helix generated and related to itself by 3 2 symmetry.In the high-temperature polymorph, the two helices become additionally related to one another by 6 2 symmetry, which maps all of the atoms in either chain onto the other chain after rotating by 60°and translating 1/3 through the cell (Figure 1 left).At low temperature the F atoms become ordered, and the 6 2 symmetry is lost, leaving only the 3 2 symmetry.